On 25/5/09 17:45, David Booth wrote:
On Fri, 2009-05-22 at 20:49 +0200, Dan Brickley wrote:
On 22/5/09 19:47, Pat Hayes wrote:
David Booth wrote:
Yes, that's a great topic for discussion. It is clear that semantic
drift is a natural part of natural language: a word that meant one thing
years ago may mean something quite different now.
And the same is happening with URIs.
[ . . . ]
foaf:schoolHomepage. This is a property originally created by brits for
whom School is where you go until you're at most 18. After which it's
off to University, College, Tescos, or whatever YTS schemes are called
these days. *However* ... shortly after deploying foaf:schoolHomepage,
it became clear that it meant something quite different to USAmericans
and presumably others. We started seeing instance data where people were
asserting foaf:schoolHomepage between themselves and the homepage of
their University. This was unexpected, but not really suprising.
Being a pragmatist, I updated
http://xmlns.com/foaf/spec/#term_schoolHomepage ...
It now mentions this drift explicitly: "The original application area
for foaf:schoolHomepage was for 'schools' in the British-English sense;
however American-English usage has dominated, and it is now perfectly
reasonable to describe Universities, Colleges and post-graduate study
using foaf:schoolHomepage."
That's an interesting example. As described, it sounds like the
American interpretation was actually *consistent* with the original
definition, but the original definition meant different things to
different readers, and the original authors had not anticipated this.
[lang=EN-uk]
Well, if the original text was EN-uk, "school" meant school. However it
turns out that in the RDFS I never set an xml:lang language on the text
literals defining the properties. And in the HTML variant of the spec it
only says 'xml:lang="en"'. Future versions should probably pick which
flavour of the language to use, ... but also it should avoid using words
whose interpretations vary :)
That example does not sound at all like an argument against semantic
anchoring. Rather, it sounds like an example in which a URI declaration
turned out to be less constraining than originally thought. The point
of a URI declaration is not to forbid semantic variability, it is to
permit the bounds of that variability to be easily prescribed and
determined.
[ . . . ]
In short, although semantic web architecture could be designed to permit
unrestricted semantic drift, I think it is a better design -- better
serving the semantic web community as a whole -- to adopt an
architecture that permits the semantics of each URI to be anchored, by
use of a URI declaration.
And I disagree.
Seconded. But perhaps for different reasons. We need to leave some
flexibility in the system so that the most useful uses of classes and
properties can emerge from experimentation and deployment.
Again, the point is not to *forbid* semantic flexibility, but to permit
that semantic flexibility to be clearly constrained. There *are*
important use cases in which it is advantageous to evolve a URI
declaration over time, or to have an intentionally broad URI
declaration.
OK, we're not disagreeing heavily then.
cheers,
Dan
